Wireless receiver



Feb- 18, 1941- P. R. DuKs'n-:RHuls Erm. 2,232,217

WIRELESS RECEIVER Filed m13Y 22, 19:59 sheets-Shaq L NvENToRs ATTGRNEY.

Feb. 18, 1941. P. R. DUKsTERHUlS ml.' 2,232,217

WIRELESS RECEIVER Filed July 22, .1939

4 Sheets-Sheet4 2 (LVM,

ATTORNEY.

Feb.18,1941. 'P RDUKSTEHUIS m.. 2,232,211

WIRELESS` RECEIVER Filed July 22, 1939 4 Sheets-Sheet 3 Feb 18 1941-v P.R. DIJKsTEm-luls r-:rAL 2232.217

I WIRELESS RECEIVER Filed July 422, 1939 4 sheets-sheet 4 ATTORNEY.

Patented Feb. 18, 1941 UNITED STATES PATENT OFFICE winEILEss nEoElvEnApplication July 2z, 1939, serial No. 285,888 i In the Netherlands Julyz3, 193s 4 claims.. (ol. 25o-4 0)- This invention relates toa wirelessreceiver for reception of a pluralityof wave length ranges which iscapable of being automatically tuned to a number of predeterminedstations by means '5 of a' station selector constituted, for example, by

a keyboard. Such a station selector greatly facilitates tuning since fortuning'to a given station it is ronly necessary to press the memberassociated with -that station such, for example, as -a key with theresult that the tuning condenser reaches automatically the tuningposition vof the said station. Since, however, the stations to beselected by the station selector are distributed about a plurality ofwave length ranges, generally about the long wave and the intermediatewave regions, it is necessary for the user always to operate the wavelength switch as well, which involves a complication in the control ofthe set. This disadvantage is obvi-ated by the present invention. Y

The wireless receiving vset of the kind described above is characterizedin that the said keys also cooperate vwith the wave length switchpresent in the set in such manner that upon operation of some key theset issuitable for reception on the wave length range corresponding tothey said key. So the operation of the wave length switch as asupplementary operation in tuning to a station by means of the stationselector prior tothe operation of a key is entirely omitted. Tuning isthus v rendered substantially simple.

The arrangement may be carried into practice in a great variety'of ways.Thus, for example, according to the invention it is possibleto provideeach of the keys with one or more stops capable of being adjustedrelatively to the operating mechanism of the wave length switch, thewave length switch being caused to occupy the `desired position whilethe key concerned is being 40 forced in or subsequently to that, throughthe cooperation of the said stop or stops and the said mechanism.` Insuch a construction it is possible in various ways to construct thestop-,or stops to be adjustable. Thus, for example, it is possible toconstitute the stop by a stylus Aor other member capable of beingdisengaged from the key and of occupying various positions relatively tothe key and also relatively to the operating mechai nism of the wavelength switch due to the presence'of a plurality of apertures in thekey. In a further embodiment the stop will always occupy a stationaryposition relatively to the key and adjustment of the key to another wavelength range is eiiected byrotation of the key, about its long $5 axis.

The cross section of the said stop may be wedgeshaped in such mannerthaton the key being forced-inv the stop pushes away the operating member ofthe wave length switch. The operating mechanism of the wave length maybe .i5 shaped in dierent forms.

In a convenient embodiment of the set according to the invention theoperating mechanism of the. wave length switch is slidable and moves the.wave length switch into the desired position by `10 the shiftingconsequent upon the engagement of thestop by thev forced-in key. A verycomiact formV of construction is obtained in a further embodiment inwhich the center lines of the keys vfollow a straight-line in parallelwith which the 15 keys describedr above is provided with a removablemember and in which the keys are arranged on a row a number of railscorresponding to the number of wave ranges to be covered is arrangedparallel with the said row` in such manner thatL30 the ends ofthe-removable stops cooperate, in each of their positions in one of thekeys, with one of the said rails'. In this case each of the rails may beunited to a lever which moves the wave length switch into the' desiredposition.35 Thekeys will generally be arranged in'a straight -line butit is also possible to arrange them to follow a curved line, the busbarsbeing curved in a corresponding manner.

In a `further embodiment the end of each of ,40 the stops in each of thekeys cooperates with a change in prole of` a member arranged parallelvwith the keys so that forcing-in of one of theA keys in accordance withthe position' ofthe stop or stops has the effect of shifting the saidmember 45 and thus oi changing the wave length switch.`

In a further embodiment the operating mechanism of the wave lengthswitch is formed by a scissor shaped member whose blades have correlatedmovements, for example by means of gear 50 .wheels, and are arrangedside by side, the arrangement being such that by adjustments of themember in one of the keys which cooperates with the said mechanism, thismember engagesv either the one or the other blade. l 55 In order thatthe invention may be clearly understood and readily carried into effectit will now be described more fully with reference to the accompanyingdrawings.

Figs. 1, 2, 3, and 4 show one form of construction of thedeviceaccording to the invention; Figs. 5 and 6 illustrate diagrammaticallyanother form of the invention using a different type of switch controlbut the same type of holding means; Fig. '7 illustrates a modication ofthe invention using a displaceable .rocker bar; Figs. 8, 9 and 10 aredifferent vie-wsof a system constructed according to the invention andemploying a plunger type of switch control device; Figs. 11 and 12illustrate a modification of the invention wherein lateral displacementof the switch control mechanism is produced; and, Fig.

13 illustrates a modification of the invention em ploying a scissorstype of switch control.-

The shaft I which carries the rotary part of tuning condenser hasmounted on it a pinion 2 which engages a toothed sector 3 which can bemoved by a lever 4 pivoted at 5. This lever is always forced upwardly bythe action of a spring 6. This lever is engaged by the end of the shaft1 of a key 8. The part 9 which is adapted to rotate in the shaft 1 maybe lengthened or shortened by means of a set screw I8 and thus permitsof varying the'rotation of the shaft I and hence the tuning when the key8 is forced-in.

A wireless set generally comprises a number of such keys, said keyscorresponding generally to the stations in various wave length ranges.By adjusting the part 9 the user of the set can himself always determinewhich stations he desires to receive automatically by means of the keysby forcing-in the key concerned. The presence of the device describedhereinafter which, upon a key being forced in, movesl the Wave lengthswitch into the position associated with the station selected avoids theneed for moving the wave length switch as a supplementary operation inaddition to forcing-in a key.

This device comprises-a stop II which, when the set can be switched tostations in two wave length ranges. can be inserted in one of the twoapertures I2 and. I3 that are formed in the key-shaft 1. These aperturesare clearly shown in Fig. 4, which is a side view of the key 8 and thekey-shaft 1. Fig. 1 shows the stop II' inserted in the aperture I3 andin .dotted lines the manner in Which the stop Il can be inserted in theaperture I2.

Whereas in Fig. l the key 8 is shown at rest, Figs. 2 and 3 show thiskey in forced-in position, the stop I I h-avingengaged one of the armsI4 of a bell crank which is pivoted at I5 and the other arm I6 of whichis connected .to the wave length switch (not shown), for example lbymeans of a Bowden cable I1. A comparison of Figs. 2 and 3 reveals thatwhen the stop II is inserted in the aperture I3 the bell crank turnsthrough a substantially larger angle a than when the stop II is insertedin .the aperture I2 with lthe result that the lever has turned throughan angle b. Due to this difference in yangle values the wave lengthswitch occupies a different position in the two cases so that the eectdesired is obtained. For the sake of completeness this figure shows inaddition the device by means of which the key maintains its forced-inposition. For this purpose the key shaft 1 has secured to it a truncatedmember I8 which, when the key is forced-in, is maintained in thisposition by a lever I9 which locks the member I8 under the pull of aretractbuttons comprising a locking device 24 which is .similar to thatshown in Figs. 1 and 2 and for this reason will not be described here ingreater detail. rThe key-.shafts 25 and 26 carry a wedgeshaped member21,128 which will always occupy a stationary position relatively to thekey-shaft 25 and 26 but are enabled, by a rotation of the keys 22 l.and23 through 180, .to occupy a different position relative vto theoperating mechanism 29 of the wavelength switch. This operating membercomprises a strip 30 which has formed in it aperturesl which aresituated below the members 21 and 23. The strip 3D is maintained'in itsmid-position under the pull .of two retracting springs y32 and 33.- Whena key as, for example, the key 23 of Fig. 6 is forced in thewedge-shaped member 28 engages the side 34 .of the aperture 3I andV onthe key being forced into a further eX- tent it pushes the strip 30 tothe right. This has the effect of also moving a lprojection 35 on thestrip 30 to the right and of .thus pushing to the right the arm 38 ofthe switch thus connecting larm 38 to right-hand contact ofthe wavechange switch 31. As soon as the key 23 returns to its off-position thestrip 30 moves again to its midposition under the pull of the springs 32and 33. Obviously, Von the key 22 being forced-in the strip 38 is movedto the left with the result that the switch arm 36 is connected to theleft- ;hand `,con-tact of the wave length switch. 'As ,stated before,the wave length switch is changed v`overto the other side when one ofthe keys 22 and 23 is rotated through 180 about its long axis.

The keys have naturally to be arranged in such mannerv that they cannotbe rotated by accident. This may be ensured by suitable locking.` Thus,

Vfor example, it is possible to construct the knobs of .the keys, so asto be square and to bring them `together very closely so that the keysprovide themselves for locking against rotation of the Yneighboringkeys.

Fig. 'IA shows the system of Figs. 5 `and 6 except .that Athe lockingdevice 24 and the wave length switch operating mechanism are united toform a single member. For this .purpose the member 40 not only isrotatable .on the shafts 38 and 39 according to the arrow A but is alsoslidable on them endwise according to the arrows B. Each of the keys ofwhich only two, 4I and 42, are

on the shafts 38 and 38. At thesame time the `rear-side of the member 43has been shifted on the inclined part 48 of the rocking member and hasthus moved this rocking member backwards with the result that the edge48 of the recess 41 rclasps the upper side of the member 43, which isalso due to the action of a compression spring 50. This ensures lockingof the key 4I, while at the same time the `displacenient to the leftmentioned before of the rocking member causes the contact 54v to engagecontact 55. It should be noted that contact 54 is mounted on the rockingstrumentality by a conductor 52 Whereas contact 55 is connected to thewave length instrumentality through conductor 52. By cooperation of thecontacts 5| on the right hand side of the rocking member and the contact53, the receiver is adjusted for tuning to a different wave length upondisplacement of the rocking member to the right as by depression of pushbutton 42. Compression spring 58 tends to force rocker 40 outwardly asviewed in Figure 7. However, spring 50 has no eiect upon the axialdisplacement of the rocker lill. In other words, once rocker 40 isdisplaced axially to either the position wherein contact 54 engagescontact 55 or the position wherein contact `5| engages contact 53, itremains in that position until it is moved out of it Vby depression of apush button which will cause it to move to the other position. Thus,assuming the key 4| is depressed and that because of the angularposition of member 43, rocker bar 40 is moved over tothe left, it willnot return to its center position even though the top portion `of member43 falls below the lower surface .of 46 when key 4| is depressed to itsfull extent. Upon depression of key 42, key 4| will be released due torotation vof rocker bar d against the force of spring 50 and rocker bar48 is moved over to the right hand position vdue to the angular positionof member 44 whereby engagement between `contacts 54 and 55 is brokenand contact comes into engagement with contact 53. v

Figs. 8, 9 and 10 show a third form of construction of the deviceaccording to the invention which comprises a number of press buttons 56having each two bores 51 and 58 formed in it, it being possible, as isclearly seen in Fig. 9, to insert in them a stud 59 havinga forked end60 (Fig. Each of the press buttons comprises a key shaft 6| adapted tocooperate in some manner with the tuning members of the set. Two rails62 and 63 are arranged parallel with the row of press buttons andrespectively in front of and at the back of the key shafts 6 I, saidrails being interconnected by levers 64, 65 and 66, 61 respectivelywhich are urged by springs. Under the action of the springs 68, 69 and10, 1| respectively said rails will always be maintained in the positionsho-wn in Fig. 9 for the bus-bar 82. When one of the keys, in Figs. 8and 9 the key 58', is forced-in the forked end 6|) o-f the stud 58 inthe forced-in key engages one of the rails, in the figure bus-bar 63,with the result that the levers by which this bus-bar is supported arerotated against the action of the spring and thus operate the wavelength switch through the intermediary of a pull cable 12. Theretracting springs ensure that when a key returns to its off-positionthe wave length switch also returns to its mid-position. In this system,a plurality of wave length ranges may also be selected withoutdifficulty, such selection depending on the number 0f rails and thenumber of apertures in the keys.

Figs. 11 and 12 show a further form of construction of the device inwhich each of the keys 13, which are arranged on a row, has two adjacentapertures '14 and 15 formed in its shaft part. The stud 16 can beinserted in said apertures. The stud is designated in Fig. 11 for eachof the keys by a black dot. At the side of the row of keys is arranged aslidable member 11 of which Fig. 12 is a cross-sectional view. Thismember has formed in it a number of apertures 18 which are tapereddownwardly in the shape of an edge: The-member -11- has connected to ita l'ever'19which' cooperates with the'switch arm 80 y'of the wave length'switch 8|. The slidable member 11 is maintained in its mid-position byrtwo retracting springs 82 and 83. When one of the knobs is forced-in thestud 16 mounted in thev knob vwill move the member r11, by means of itsend, to the left or to the' right according as the stud isarranged inthe left hand or in lthe right hand aperture in thekey shaft, with theresult that the wave length switch arm 80 is moved to the left or to theright. The presence of the horizontal extensions of the apertures 18ensure thatthis shifting of the member 11 will take place in anunhampered manner in spite of the presence of the studs 16 in the keyswhich are not forced-in. This embodiment may also be conceived of insuch manner that the studs are not removable from the key shafts but areadjustable therein.

lig. 13 shows a further form of construction of the wave length switchoperating mechanism, the latter being formed by a scissor-shaped memberthe blades 84 and 85 of which are coupled in their movement by gearwheels ||l| and |92 which engage eachother. The blades 84 and 85 arepossessed of projections arranged side by side. Thus, for example, theblade 84 in the embodiment of the figure carries projections 86, 81 and88 and the blade 85 projections 89, 90 and 9|. The keys 92, 93 and 94arranged in front of the blades carry projections 95, 96 and 91 on theirshafts. Comparatively small rotation of the keys about their shafts, forexample through an angle of 30 degrees, permit these projections to beshifted in such manner that, on the keys concerned being forced-in, theyengage a projection' of they other scissor blade instead of that of theoriginal blade with which they cooperated. The figure shows in additionthat the shaft of the lower scissor blade is coupled to a lever 98 whichoperates the wave length switch (not shown) by means of a cable 99.Under the action of a spring (not shown) the scissor mechanism willalways be maintained inthe position shown, when none of the keys isforced-in. If,- for example, one of the projections of the scissorblade85 is forced-in then the lever 98 of the wave length switch moves in thedirection of the arrow A, the gear wheel |02 driving the gear wheel IUIand the scissor-blade 84 moving upwardly. If on the contrary one of theprojections of the scissor blade 84 is operated then the scissor blade84 is lowered with the result that the gear-wheel Il rotates the gearwheel |02 and the lever 98 is moved in the direction of the arrow B.

It is also possible to arrange the device in such manner that inoff-position of the keys the projections thereof are out of range of theupwardly-moving projections of the scissor blades.

I claim:

1. In radio receiving apparatus which is provided with an automatictuning instrumentality including a plurality of station selecting pushbuttons and a wave band changefover switch for adjusting the receiver totune over any one of a plurality of wave bands, at least one of saidstation selecting push buttons being rotatable about itsv axis tovarious different positions, single means operable upon operation ofsaid push button for controlling the operation for said change-overswitch and for holding said push button in a depressed position untilthe subsequent operation of another push button,

said means being arranged so as to operate the change-over switch sothat the wave length to which the receiver is tuned upon depression ofsaid push button when the push button is in one of its angular positionsis in one of said plurality of Wave bands and to operate the change-overswitch so that the wave length to which the receiver is tuned upondepression of said push button when the push button is in another of itsangular positions is infanother of said plurality of wave bands.

2. The arrangement described in the next preceding claim characterizedby that said single means comprises a rocker bar assembly which upondepression of said push button is rocked about its axis and axiallydisplaced in one direction when said push button is in said first namedangular position, and in the other direction when said push button is inthe second named angular position.

3. In a tunable radio receiver which is provided with a push buttontuning instrumentality and a selectively operable wave band change overswitching means for adjusting the receiver to tune to signals within anyone of a plurality of wave bands, operable means for operating saidswitching means and for locking any depressed push button of said tuninginstrumentality in a depressed position until the subsequent operationof another push button of said tuning instrumentality, said operablemeans including an axially displaceable rocker bar capable of beingrocked about its axis between a latching position and a releasingposition and axially displaced from a position wherein the switchingmeans is operated so that said receiver is adjusted to tune to signalswithin one of said wave bands to a position wherein the switching meansis operated so that the receiver is adjusted to tune to signals withinanother oii said wave bands, means for urging the rocker bar to itslatching position, individual means for each of said push buttons eachacting upon depression of its related push button to first rock saidrocker bar to its releasing position whereby any previously depressedpush button is released, thereafter release the rocker bar whereby therocker .bar 'returns to its latching position and finally 4cooperatewith the rocker bar to hold its push Abutton in a depressed positionuntil released by the subsequent `operation of another push button, atleast one of said individual means being independently adjustable tovarious vdifferent positions and arranged so that upon depression `ofits push button it causes displacement of said rocker bar to an axialposition depending upon the adjustment of said individual means.

4. In a tunable radio receiver which is provided with a push buttontuning instrumentality .and aA selectively operable wave band changeover switching meansv for adjusting the receiver to tun'e to signalswithin any one of4 a plurality of wave bands, operable means foroperating said switching means'and for locking any depressed -pushbutton of said tuning instrumentality in a kdepressed position until thesubsequent operation of another push button of said tuninginstrumentality, said operable means including a 4rocker bar arranged soas to be rocked about its axis between a latching position and areleasing position, said rocker bar being also axially displaceablebetween a position wherein the receiver is vadjusted to tune to signalswithin one of said wave bands and a position wherein the receiver isadjusted to tune to signals within another of said wave bands, meansurging said rocker bar to its latching position, at least one of theypush b POPKO REINDER DIJKSTERHUIS.

MAARTEN JAN GROENENBERG.

JAN TIMMERMAN.

W'ILHELMUS LAMBERTUS LEONARDUS VIVIE.

